An accounting firm needs to allow users to update records simultaneously without errors.

A database is the best solution for allowing multiple users to update records simultaneously without causing errors. Databases, especially relational databases like MySQL, PostgreSQL, and Microsoft SQL Server, are designed for concurrent access, ensuring data consistency and integrity through mechanisms like transaction management and locking.

A. Flat file does not support concurrent access efficiently, making it unsuitable for simultaneous updates.

B. Document formats like Word or PDFs are not designed for simultaneous multi-user editing.

D. Spreadsheet programs like Excel can allow multiple users to view data but are prone to errors when used for concurrent data updates.

References:

CompTIA IT Fundamentals (ITF+) Certification Guide

Official CompTIA Database Fundamentals Study Materials